The Aim: This study aimed to evaluate the effectiveness of Marsupialization on different jaw cystic lesions by volumetric analysis using three-dimensional computed tomography (CBCT). Patients and Methods: Fifteen patients were enrolled for this study. All patients underwent surgical Marsupialization of different jaw cystic lesion. Preoperative CBCT for all patients was compared to their postoperative views after follow up period ranged from 6 and 24 months. Three dimensional volumetric analysis was performed for all cases to assess the differences in volumetric change rate, initial volume of the lesion, duration, location of the lesion, and pathological diagnosis. Results: All cystic lesions showed great reduction in size measured on CBCT. There were no important surgical complication recorded throughout the study. The reduction rate among all patients ranged from 58.83 – 73.56 %. The results showed that higher reduction rates were associated with a long marsupialization period, and younger patient age. Conclusion: Marsupialization is a valuable treatment option for different jaw cystic lesion especially with large size in all patients. The effectiveness of this treatment modality is proportional to long treatment duration, younger age group of the patients, as well as nature of the cystic lesion.